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Signs of Free Peritoneal Air

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Essential Radiology Review
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Pneumoperitoneum is defined as free air in the peritoneal cavity. It is most commonly caused by rupture of a hollow viscus such as gastric or duodenal ulcer perforation. Other common causes include feeding tube insertion, bowel anastomotic leak, barotrauma, and intra-abdominal surgery. After a laparotomy, air is usually present for 3–7 days and should not increase in volume. An upright PA chest radiograph is traditionally the initial examination unless a patient is critically ill. In that circumstance, a supine decubitus radiograph is preferred. The diagnosis of pneumoperitoneum is critical because it is usually an indication for emergent surgery with exception of benign etiologies of free air. On radiographs, the signs of free peritoneal air are subtle and diverse. There are four major groups that these signs are categorized into: bowel-related, right upper quadrant, peritoneal ligament-related, and other signs.

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Bahouth, S.M. (2019). Signs of Free Peritoneal Air. In: Eltorai, A., Hyman, C., Healey, T. (eds) Essential Radiology Review. Springer, Cham.

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  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-030-26043-9

  • Online ISBN: 978-3-030-26044-6

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